The present invention relates to gas heated broilers for meat products and the like, and more particularly to apparatus and methods for reducing harmful emissions of smoke having pollutants such as grease and other hydrocarbons entrained therein.
Broiler smoke is often objectionable, producing eye irritation and other discomforts, as well as blocking clear view of cooking in progress. Also, recent regulations in many jurisdictions impose limits on airborne particulate and other pollutant concentrations in restaurants and other places that operate broilers, with consequent requirements for pollution control equipment. For example, the Southern California Air Quality Management District (SCAQMD) generally requires permits and registration fees for commercial broiler operation, and the use of Best Available Control Technology (BACT) emissions control equipment.
Broilers having provisions for reducing the production of smoke are known, being disclosed in U.S. Pat. Nos. 4,899,724 and 5,117,747 to this inventor, which are incorporated herein by these references. These devices of the prior art have significant advantages in reducing grease-laden smoke in restaurants and other environments where broiling of meat is practiced. The ""724 patent discloses a broiler having inverted V-shaped radient heat transmitting elements or radiants positioned above respective gas burner tubes of the broiler, and a thermostatically controlled regulator for controlling the temperature of a cooking zone of the broiler. The ""747 patent discloses a broiler having laterally spaced grill sections, burner tubes spaced below and between the grill sections, inverted V-shaped radiants above the burner tubes, deflector members above the radiants for deflecting converted heat laterally outwardly onto the grill sections, and baffle elements above the deflector elements and between the grill sections for preventing grease from dripping onto the deflector elements. Also, an inclined drip pan is located below the burner tubes, and water is circulated in contact with the underside of the drip pan to the upper extremity, the water trickling downwardly on top of the drip pan to carry away drippings from beneath the grill sections. Unfortunately, these devices also have a number of disadvantages; for example:
1. They are expensive to provide, particularly when configured with multiple grill sections;
2. They have objectionably non-uniform heat distribution across the grill sections, particularly when the broilers are configured with wide grill sections and correspondingly extended spacing of the burner tubes in order to reduce manufacturing costs;
3. They are unsightly, particularly when not in use carrying a load; and
4. They are ineffective in that cooking is slow.
Thus there is a need for a vehicle cargo carrier that overcomes the disadvantages of the prior art.
The present invention meets this need by providing a broiler that is particularly effective for fast production without producing flaming grease or smoke clouds, yet is relatively inexpensive to provide. The broiler includes a cabinet structure having an upwardly facing grill opening; a grill extending across the grill opening for supporting the meat products; an elongate heating element spaced below the grill; an elongate radiant element spaced between the heating element and the grill for directing heat laterally from above the heating element; an inclined trough member having a coolant passage being spaced between the grill and the radiant element for preventing grease from dripping on the radiant element and the heating element; means for feeding liquid coolant through the coolant passage; and means for directing grease from a lower end of the trough member to a region below the heating element without contacting either of the radiant element and the heating element. The coolant passage can extend from an inlet port preferably located at the lower end of the trough member to an outlet port at an opposite upper end of the trough member for counterflow of the liquid coolant relative to grease traveling in the trough member toward the lower end thereof. Preferably the inlet and outlet ports of the coolant passage are laterally centered relative to the trough member, a laterally spaced pair of trough surfaces being formed therein, the outlet port being located proximate an upper end extremity of the coolant passage for facilitating maintenance of the coolant passage in a filled condition.
The means for directing grease from the lower end of the trough member can include a laterally downwardly sloping chute member, or a pair of oppositely laterally downwardly sloping chute members for receiving grease from the pair of trough surfaces, exit extremities of the chute members being spaced laterally beyond side extremities of the heating element and the radiant element.
Preferably the broiler includes a heat sensor for sensing temperature of a region proximate the grill, and a control device for controlling heat flow from the heating element in response to the heat sensor. The heating element can include a gas burner tube. Preferably the burner tube has respective gas emitting ports oppositely inclined laterally outwardly and upwardly for producing a spaced pair of outwardly and upwardly directed flames. The gas emitting ports can be configured as respective rows of openings. The gas emitting ports preferably an included angle of inclination being between 30 degrees and 90 degrees and a lateral port spacing of between 0.4 inch and 1.0 inch. More preferably. the included angle is approximately 60 degrees and the lateral port spacing is approximately 0.6 inch. Preferably the burner tube has an inlet end and a closed end, the closed end being under the lower end of the trough member for facilitating direction of the grease from the trough member away from hotter regions of the broiler.
The radiant element can include a laterally spaced pair of sheet members, respective main portions of the sheet members preferably sloping upwardly and inwardly for directing radiant heat upwardly and outwardly from the heating element. Preferably the radiant element has respective flue portions of the sheet members extending vertically upwardly from upper extremities of the main portions for producing upward convective flow over the sheet members. Preferably a shield element is spaced between the radiant element and the trough member for limiting heating of the trough member. The shield element can include a horizontally oriented strip, which preferably has a pair of downwardly extending lips formed along side extremities of the strip for redirecting the convective flow outwardly and downwardly from upper extremities of the radiant element sheet members.
Preferably the broiler also has a sloping drip pan spaced below the heating element; a grease collector for collecting grease from a lower extremity of the drip pan; and means for feeding the liquid coolant from the coolant passage in contact with a bottom surface of the drip pan for cooling the drip pan, the liquid overflowing onto a top surface of the drip pan for washing grease into the grease collector. The means for feeding the liquid coolant can include a plenum chamber formed under the drip pan, and a coolant conduit having an outlet located in the plenum chamber near a lower extremity of the drip pan, the coolant conduit being connected to coolant passage of the trough member. Typically there are horizontally spaced plural counterparts of the heating element, the radiant element, the shield element, and the trough member.